From least to greatest:

• Desert Robot Commandos
• Jump Chip
• Old Macdonald vs Zombies
• Starbeard: The Curse of the Space Whales
• Uno Terra
• Lestac
  For more info on Lestac’s development: lestac.net
• Jameson the Pilot
  For more info on Jameson the Pilot’s development: jameson.rezoner.net

You can play One Shot Showdown (the game I made) here.